Worm wheel



Patented Apr. 6, 1926.

' JAMES s Q i Wmwensue/ re am,

HALF so JAMES; was?lsamme :OF, mwl ssevmisevmuawe 71 1 I or power;

I n pncanonnua Main, 1923. serial-no. 639,596.

To all whom it Witty/009166771) 7 Be it known that I, JAMES. LAX,'a'subject of the King ofGreatBritain, and-resident" of Johannesburg,Transvaal Province, Union.

of South Africa, have invented certain new and useful Improvementsi-nWVorm Wheels, of which the following is a specificationi Thisinvention appertains to worm-wheels,

or to wheels whichareiem'ployed with worms or' the like for thetransmission of rnotion The invention has forits o bject -to timstruct aworm-wheel insuch away as to min- .imize the'fri'ction engenderedbetween"the worm and worm-wheel, or so asitoobtain a practically frictionlesstransmission of the 'power-or motion from'* the worm-toltheworm-wheeland to allow of-a ny loo'seness in the working-parts -beingtaken'iup.

To the attainment of thisobjefctt-he in vention consists, 'broadly,;linconstructing or providing a wormewheel with teeth" or their equivalentwhich are adapted to rotate independently of each other about their ownaxes when in engagement with the worm and in providing means whereby anylooseness or play in the bearings of the teeth can be taken up. i

The invention will be described in detail in connection with theaccompanying drawings, wherein a practical embodiment of the inventionis illustrated.

In-the drawings,

Fig. 1 is a side part-sectional elevation of portion, of a worm-wheelconstructed according to one form of the invention.

In constructing the improved worm-wheel in the form illustrated, acentre piece 1, in the form of a disc, as shown, is employed, or it maybe a rim connected by spokes to a hub or centre piece. Around theperiphcry of the disc 1 there is formed a number of radial holes orrecesses 2, the distance said holes 2 are apart circumferentially of ofthe disc 1 being determined bythe pitch therefrom and the outwardlyprojecting part of which forms the tooth; The tooth portion is madeofcircular cross-section, and

is curved from near the periphery of the disc 1,'=or" root orhase 'of-the"'tooth,- to' balls 6 arranged betweensaid "annular-fpro ection 4and-the" bottom' of-the recess 5.

" The'i nner portion of the pin'3 is rotatable 7 in the hole 2, audit-heinner end-.7 of the pin 3, near the bottom of thehole 2",i's fo'rmedwith 'anannulargroove 8 to provide a race fora ring" of balls ,9 placedbetween said inner end? and the wall of the hole 2-'near' the inner endthereof. A part ofthe-inner? portion ofthe pin 3;isreduced in diameter,

as indicated at9 and aroundsaid reducedportion there isarrangedata fred-sleeve ormember l0-having its taper 1n the direction' 5dr: the outerend ofthe pinor tioo'tlrB. 1

The outer'end of the tapered-sleeve 10*isformedwitlr a: flange ll whichfits theh'ole- 2 and the inner 'endof said s'leeve =10 is by forcingsaid sleeve members 10 inwards,

thus retaining the pins 3 in their respective adjacent holes 2. Thetapered .pins 13 and the tapered sleeves 10 provide an easily operatedmeans for obtaining nice adjustment of the pins 3 to allow of freerotation thereof and to take up any looseness' or play in the ballbearings 6 and 9, at the inner ends of the pins3 and bases of the teeth,respectively.

- Worm-wheels according to the invention maybe adapted to work withsingle or multiple threaded worms. 1 'As the friction between the wormand worm-wheel is minimized, the worms can be made of brass orlike metalwhich can be cut or: shaped more quickly than steel, of which worms areat present most commonly, constructed,

As the teeth or pins of a Worm-Wheel constructed according to theinvention are preferably all turned, the use ofv hobs, as at presentused to cut the teeth of Worm- Wheels, is obviated.

With the improved Worm-Wheel the efficiency of the transmission is notimpaired should the Worm shaft not be exactly at right angles to theWheel shaft, as the contact between the Worm and worm-Wheel is onlyalong a line.

The necessity for special means of lubrication, such as an oil bath isavoided, and also the necessity to arrange the Worm to engage with theunderside of the worm- Wheel.

The improved Worm-Wheel is easily manufactured as compared With ordinaryworm- Wheels, and its manufacture does not call for the use of expensivemachine tools.

What I claim as my invention and desire to protect by Letters Patentis 1. A Worm-Wheel or the like, comprising a centre portion, a pluralityof rotatable teeth disposed around the periphery of said centre portion,said teeth being in the form of radially disposed pins partially housedin holes formed around the periphery and 7 said teeth being adapted torotate independently, anti-friction bearings for each tooth positionedintermediate the tooth and its housing in the centre portion, andadjustable means in the form of a locking pin arranged transversely ofthe pin for reta'ining the pin in its housing in the centre portion, asset forth.

2. A Worm-Wheel or the like, comprising a centre portion, a plurality ofrotatable teeth disposed around the periphery of said centre portion,said teeth being in the form of radially disposed pins partially housedin holes formed around the periphery and said teeth being adapted torotate independently, anti-friction bearings for each tooth positionedintermediate the tooth and its housing in the centre portion, andadjustable means for retaining the pins in their housings in the centreportion, said means including a sleeve arranged around each pin and alocking pin arrangedtransversely of the pin co-operating with saidsleeve to adjust the pin, as set forth. 7

3. A Worm-Wheel or the like, comprising a centre portion, a plurality ofrotatable teethdisposed around the periphery of said centre portion,said teeth being in the form of radially disposed pins partially housedin holes formed around the periphery and said teeth being adapted torotate independently, anti-friction bearings for each tooth positionedintermediate the tooth and its housing in the centre portion, and meansfor adjustably retaining the pin in its housing in the centre portion,said means comprising a tapered sleeve surrounding part of the innerportion of the pin, and a tapered pin engaging With the centre portionand said sleeve, as set forth. I

In testimony whereofl have signed my name to this specification,

JAMES LAX.

